Cells, tissues, organs, and organisms that are deprived of appropriate blood flow undergo ischemic damage due to oxidative stress and eventually die. Traditional methods of reducing ischemic damage involve perfusing affected tissues with oxygen, but this procedure can cause significant tissue damage and can result in serious and/or permanent injury, such as brain damage during stroke or cardiac arrest.
Attempts have been made to reduce ischemia and reperfusion injury by inducing tissues and organs to enter a reduced metabolic state. In the context of living tissues being preserved for transplant or grafting, one common method for reducing their metabolic activity is by immersing tissues or organs in a physiologic fluid, such as saline, and placing them in a cold environment. However, such methods cannot be relied upon for extended periods, and the success of organ transplant and limb reattachments remains inversely related to the time the organ or limb is out of contact with the intact organism.
Separately, oxygen deprivation can also occur in living organisms when the lungs are improperly functioning or not functioning at all. One approach to improving oxygenation in patients is through the use of extracorporeal membrane oxygenation (ECMO), in which venous blood is extracted from the patient, passed through a membrane oxygenator, and then returned to the patient. The ECMO system may include filters or other components which are used to remove blood clots and other biological materials that may need removal before blood is reintroduced into the patient thereby avoiding clogging of the ECMO system, in particular clogging of the membrane oxygenator. There is a need to improve existing ECMO systems and methods to avoid this clogging.